A systematic review of highly purified cannabidiol in developmental and epileptic encephalopathies and complex treatment-resistant epilepsies: Nonseizure outcomes.

OBJECTIVE

A plant-derived, highly purified cannabidiol (CBD) oral solution (Epidiolex® [US]/Epidyolex® [EU]) is approved for the treatment of seizures associated with Lennox-Gastaut syndrome (LGS), Dravet syndrome (DS), or tuberous sclerosis complex (TSC). Improvements in nonseizure outcomes including cognition and behavior have been reported in patients with epilepsy administered CBD. This systematic literature review (SLR) evaluated studies reporting changes in nonseizure outcomes after CBD initiation in patients with developmental and epileptic encephalopathies (DEEs) and complex treatment-resistant epilepsies (TREs) other than LGS, DS, and TSC.

METHODS

An SLR was conducted in March 2024 according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Embase, Medline, and Cochrane Central Register of Controlled Trials libraries were searched for studies on TREs, CBD, nonseizure outcomes, and adverse events (AEs). Results were narratively summarized.

RESULTS

Thirty-two studies comprising 1343 patients were included. Thirty-one studies reported improvement in nonseizure outcomes in ≥ 1 patient, including neuropsychiatric function (n = 9/9 studies), cognitive function (n = 9/9), use of concomitant antiseizure medications (n = 7/8), communication (n = 7/7), behavior (n = 7/7), motor function (n = 6/6), healthcare utilization (n = 5/5), quality of life (n = 5/5), global change (n = 4/4), sleep (n = 2/2), and development (n = 2/2). Reported AEs were consistent with the known safety profile of CBD and most commonly gastrointestinal, including diarrhea (17-34%), vomiting (5-50%), and decreased appetite (7-20%).

CONCLUSION

This SLR mainly identified observational studies with moderate to high bias risk. The available evidence suggests CBD may improve various nonseizure outcomes in patients with DEEs and complex TREs, while underscoring the need for rigorous confirmatory studies.